JPH09199096A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a malfunction and minimize the deterioration of the performance of cells by communicating the information on charging with an external device, judging the adequacy for connection, and charging or discharging the cells. SOLUTION: A battery pack 1 is connected to an electronic apparatus 101 when its terminals are individually connected to the terminals of the electronic apparatus 101. The battery pack 1 is provided with a communication circuit 9, a judging circuit 13, and an insertion/removal detecting circuit 8. The judging circuit 13 makes a prescribed judging action based on the various information obtained by the insertion/removal detecting circuit 8, the communication circuit 9, a voltage detecting circuit 1, and a date/hour counting circuit, and it gives the prescribed instruction to a connection switching circuit 7 based on the judged result. A switch control circuit 6 is switch-controlled, and cells 5 are charged or discharged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chargeable / dischargeable battery pack used in an electronic device which is an external device.

[0002]

2. Description of the Related Art A battery is used as a power source for a portable terminal device, a notebook computer, or an electronic equipment device such as a camera body type VTR which places importance on portability. This battery only discharges and is, so to speak, a disposable type, or a type that can be charged and discharged and can be used repeatedly. A battery pack packed with such chargeable / dischargeable cells is composed of two terminals, a positive (+) terminal and a negative (-) terminal, and is always charged and discharged from the both terminals. 2 as represented by dry batteries
A terminal type battery pack or a terminal for controlling input and output called a control terminal is provided in addition to the positive electrode terminal and the negative electrode terminal. The voltage applied to the control terminal charges and discharges the positive electrode terminal and the negative electrode terminal. There is a three-terminal type battery pack that can control the battery.

A conventional example of a three-terminal type battery pack will be described below with reference to FIG. 13 together with an electronic device in which the battery pack is mounted as an operating power source. The battery pack 1 has a positive electrode terminal as an external connection terminal. 2, a negative electrode terminal 3, and a control terminal 4 are provided. Battery pack 1
In addition to the control terminal 4, a cell 5 that is made of nickel cadmium or lithium ion and can charge and discharge electric charge, a switch 7 as a connection switching circuit that switches the connection between the cell 5 and the negative electrode terminal 3, and And a switching control circuit 6 for controlling the switch 7 by the applied voltage. The electronic device 101 includes a positive electrode terminal 2 a, a negative electrode terminal 3 a, and a control terminal 4 a that individually correspond to the positive electrode terminal 2, the negative electrode terminal 3, and the control terminal 4 of the battery pack 1. In the battery pack 1, the respective terminals 2, 3, 4 are the respective terminals 2 of the electronic device 101.
By being connected corresponding to a, 3a, and 4a, they are connected to the electronic device 101. Positive terminal 2 of electronic device 101
The a and the control terminal 4a are electrically short-circuited internally.

The battery pack 1 is constructed so that the switch 7 can be turned on and off by the switching control circuit 6 by the voltage applied to the control terminal 4. When the battery pack 1 is not connected to the electronic device 101, no voltage is applied to the control terminal 4 of the battery pack 1, so that the switching control circuit 6 operates the switch 7
Is off, there is no potential difference between the positive electrode terminal 2 and the negative electrode terminal 3. When the battery pack 1 is connected to the electronic device 101, the electronic device 101
Since the positive electrode terminal 2a and the control terminal 4a are short-circuited on the side, the voltage of the positive electrode terminal 2 is applied to the control terminal 4 of the battery pack 1. The switching control circuit 6 monitors the voltage of the control terminal 4, and when the voltage is applied to the control terminal 4, the switch 7 is turned on. Therefore, the positive electrode terminal 2 on the battery pack 1 side serves as an output terminal, and a potential difference of the cell 5 is generated between the positive electrode terminal 2 and the negative electrode terminal 3.

In the battery pack 1, a voltage is applied to the control terminal 4 even when charging the battery pack 1, and the switching control circuit 6
To turn on the switch 7. Then, the positive electrode terminal 2 on the battery pack 1 side serves as an input terminal to charge the cell 5. At this time, a voltage higher than the voltage of the cell 5 is supplied from the electronic device 101 side to the battery pack 1 side.

[0006]

In the conventional battery pack described above, it is possible to provide a terminal called a control terminal for controlling the output of the battery, and to control the output of the positive electrode and the negative electrode of the battery by the voltage applied to the control terminal. However, there is a problem that the cell may be discharged even when a voltage is applied to the control terminal due to another factor.

Further, since charging is performed when a voltage is applied to the control terminal, there is a possibility that the cell will be charged by applying a voltage to the control terminal even if the connected electronic device is defective. There is a problem that exists.

Furthermore, a non-volatile memory can be provided on the side of the battery pack, and the charging date and time of the last cell can be written in this memory, but the management of the date and time is left to the electronic equipment device side outside the battery pack. Therefore, the charging date and time written in the memory is not always the same as the date and time of the connected electronic device, so the charging is managed based on the charging date and time of the memory on the battery pack side. In such a case, the cell is repeatedly charged at a voltage close to a full charge, and as a result, the performance of the cell is deteriorated at an early stage and the life of the battery pack is shortened.

Furthermore, since the control terminal serves as an input terminal in the battery pack when charging the cell, the information of the battery pack is not returned to the electronic device side, so charging cannot be performed under optimum conditions. There is a problem.

Furthermore, if the circuit in the battery pack is powered by the cell, the circuit in the battery pack may not work when the cell is completely discharged.

[0011]

According to a first aspect of the invention, a communication means for communicating information regarding charging with an external device, and a determination for determining suitability of connection to the external device based on the information. The determination means solves the above-mentioned problem by performing control to discharge the electric charge from the cell to the external device determined to be suitable for connection.

According to a second aspect of the present invention, there is provided communication means for communicating information regarding charging with an external device, and determination means for determining whether or not the connection to the external device is appropriate based on the information. The determination means solves the above-mentioned problem by performing control to charge the cell from the external device determined to be suitable for connection.

According to the third aspect of the present invention, there is provided a date and time counting means and a determining means for storing the date and time of previous charging of the cell, wherein the determining means is the date and time counted by the date and time counting means and the previous date and time. The above-described problem is solved by determining whether or not to charge the cell based on the charging date and time.

In the invention according to claim 4, claim 3
In addition to the configuration of the invention of, further has a communication means for communicating with an external device, the determination means,
The above-described problem is solved by receiving a command from the external device regarding charging of a cell based on communication via the communication means and performing a response operation.

According to the invention of claim 5, claim 2
In addition to the configuration of the invention, the power source of the determination means can be obtained from the external device, and communication can be performed between the determination means and the external device even when the charge capacity of the cell is significantly reduced. The above-mentioned problems are solved by making it possible to charge the cell.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a battery pack according to an embodiment of the present invention will be described in detail with reference to the drawings.

Embodiment 1 FIG. 1 is an internal circuit diagram of a battery pack according to Embodiment 1 of the present invention. The battery pack 1 according to the first embodiment of the present invention has the positive electrode terminal 2 and the negative electrode terminal 3, but instead of the conventional control terminal, the battery pack 1
A communication terminal 10 for communication with an electronic device as an external device to be connected to. The electronic device 101 is preferably a portable computer or a portable type such as a portable camera-integrated VTR that uses the battery pack 1 as a power source, or is not a portable type and uses the battery pack 1 as a power source. In addition, the positive electrode terminal 2a, the negative electrode terminal 3a, and the communication terminal 10a are provided corresponding to the battery pack 1. The battery pack 1 is connected to the electronic equipment device 101 by connecting the respective terminals to the respective terminals of the electronic equipment device 101 in correspondence with each other.

Before describing the internal circuit of the battery pack 1 of FIG. 1, the electronic device unit 101 will be described with reference to FIGS. 2, 3 and 4.
A usage example of the battery pack 1 for the above will be described. FIG.
4 is an external perspective view of the electronic device 101, the battery pack 1 and the AC / DC converter 103 used therein, and FIG. 3 is an external perspective view of the battery pack 1. Referring to these drawings, a positive electrode terminal 2, a communication terminal 10, and a negative electrode terminal 3 are provided on the front side surface of the battery pack 1. In the present embodiment, the electronic device 101 is, for example, a notebook type portable computer, and includes a main body 101a provided with a keyboard and the like, and a display unit made of a liquid crystal or the like that is hinged to the main body 101a and can be opened and closed. The main body 101a has a storage port 101c for storing the battery pack 1 which is the operating power source thereof, and a cover 101b provided therein. Although not shown, the positive electrode terminal 2a, the negative electrode terminal 3a, and the communication terminal 10a shown in FIG.
When the battery pack 1 is stored in c, the terminals of the battery pack 1 and the electronic device 101 are connected to each other, and the attachment / detachment detection circuit 8 of FIG. 1 detects this. The communication terminal 10 of the battery pack 1 is a terminal for inputting / outputting data for performing communication with the electronic device 101, and may be two or more terminals depending on the communication mode. . The electronic device 101 has a connection port 10 to which a connection jack 103a of an AC / DC converter 103 connected to a power outlet is connected as described later.
1d is deployed.

Returning to FIG. 1, the battery pack 1 has a cell 5 in which charges can be charged and discharged, and input / output between the cell 5 and the positive electrode terminal 2 (when the cell 5 is discharged, when the cell 5 is discharged, when it is input). A switching control circuit 6 configured by a semiconductor switching element such as a field effect transistor or a relay so as to switch the charging of the cell 5), a connection switching circuit 7 that controls the switching operation of the switching control circuit 6, and a battery pack. The attachment / detachment detection circuit 8 that detects whether 1 is attached to or separated from the electronic device 101, the communication circuit 9 that communicates with the electronic device 101, and the voltage that detects the voltage of the cell 5 and the positive terminal 2. A detection circuit 11, a date / time counting circuit 12 that counts the date and time when the cell 5 is charged as date and time management means, and a determination circuit 13 are provided. The determination circuit 13 performs a predetermined determination operation based on various information obtained by the attachment / detachment detection circuit 8, the communication circuit 9, the voltage detection circuit 11, and the date / time counting circuit 12, and determines a predetermined value for the connection switching circuit 7 based on the result of this determination. Is performed and the switching control circuit 6 is controlled to switch, thereby determining whether the cell 5 is charged or discharged, and is configured by a microcomputer or the like as described later.

The battery pack 1 has, in addition to the internal circuit shown in FIG. 1, a circuit for suppressing unnecessary power consumption of the cell 5 as described with reference to FIG. ing. The battery pack 1 normally supplies the power for operating the internal circuit shown in FIG. 1 from its own cell 5, but if all the internal circuits are kept in the constant operation mode, the consumption of the cell 5 is reduced. The electric power becomes large. Therefore, in order to suppress power consumption, the determination circuit 1 as a minimum circuit that needs to be constantly operated when nothing is connected to the battery pack 1 such as the electronic device 101.
3 and the detachment detection circuit 8 are selected, and operating power is supplied from the cell 5 only to these circuits 13 and 8 so that the circuits are always kept in an operating state.

In FIG. 5, the step-up / down circuit 14 for stabilizing the power supply by boosting the output of the cell 5 and then dropping it to a predetermined value, and the supply / shutdown of the power supply to the communication circuit 9 in the battery pack 1. A power supply switching circuit 15 for switching the power supply circuit is provided, and the determination circuit 13 and the attachment / detachment detection circuit 8 are always powered by the power supplied from the cell 5 via the step-up / down circuit 14. Desorption detection circuit 8 is current limiting resistor 8
The detection switch 8b has a configuration in which a and a detection switch 8b are connected in series, and the detection switch 8b is physically turned on / off depending on whether or not the battery pack 1 is connected to the electronic device 101. The communication circuit 9 is connected to the subsequent stage of the power supply switching circuit 15. The power supply switching circuit 15 is composed of a transistor 15a whose collector and emitter are connected between the step-up / down circuit 14 and the communication circuit 9, and a transistor 15b whose collector is connected to the base of the transistor 15a. The communication circuit 9 includes transistors 9a and 9b having the same connection relationship as the transistors of the power supply switching circuit 15.
And a main body 9c that controls communication. The determination circuit 13 changes the potential according to the on / off state of the detection switch 8b of the attachment / detachment detection circuit 8, that is, when the detection switch 8b is pushed and turned on when the battery pack 1 is attached to the device 101, the LOW output (connection That the battery pack 1 is connected to the electronic device 101 by inputting a potential which becomes a low level at some time.
When the detection switch 8b is turned off by being separated from the output voltage H, which is the output potential of the cell 5 via the step-up / down circuit 14,
It is determined that the battery pack 1 is separated from the electronic device 101 by the IGH output (potential that becomes high level when not connected), and a determination output corresponding to this is output to the power supply switching circuit 15 and the communication circuit 9. Is configured to. The determination circuit 13 has a microcomputer 13a, a memory 13b, and a clock circuit 13c as shown in FIG.

The determination circuit 13 performs a determination for setting the low power consumption mode and a determination for setting the normal operation mode as the determination for the power consumption suppressing operation. The clock circuit 13c of the determination circuit 13 has a low frequency (for example, kHz level).
The clock and the output of the high frequency (eg, MHz level) clock can be selected, and the microcomputer 13a
Is the microcomputer 1 in the low power consumption mode
Clock circuit 13c so as to suppress power consumption of 3a itself
The clock frequency from is controlled to drop to a low frequency. At this time, the determination circuit 13 monitors for the determination as described above by the detection switch 8 of the attachment / detachment detection circuit 8.
b HIGH output (not connected) and LOW output (connected)
It is. The detachment detection circuit 8 turns off the detection switch 8b to output a HIGH output when nothing is connected to the battery pack 1, and turns on the detection switch 8b to output a LOW output when connected. When the output of the attachment / detachment detection circuit 8 changes from the HIGH output to the LOW output, that is, when the battery pack 1 is connected to the electronic device 101, the determination circuit 13 sets the clock frequency to a high frequency to set the normal operation mode and the power supply switching circuit. 15 transistors 15a, 1
A determination output for turning on 5b is output. As a result, when the transistors 15a and 15b of the power supply switching circuit 15 are turned on, power can be supplied to the communication circuit 9. The power supply switching circuit 15 is turned on, and after a while until the circuit becomes stable, the determination circuit 13 determines that the communication circuit 9 has the main body 9
Required communication is carried out with the electronic device 101 via c.

A configuration for communication between the battery pack 1 and the electronic device 101 will be described with reference to FIG. This communication is performed using the communication terminal 10 of the battery pack 1 and the communication terminal 10a of the electronic device 101 configured as follows. Here, this communication is performed by the communication circuit 9 on the battery pack 1 side, the system IC 102a of the internal circuit 102 on the electronic device 101 side, and the nonvolatile memory 1 such as EEPROM.
02b is in charge.

CLK Clock supplied from the battery pack 1 to the device 101 DATAL Data going from the battery pack 1 to the electronic device 101 In the electronic device 101, the DATA2 electronic device 101 connected to the system C 102a and the memory 102b Data toward the battery pack 1 In the electronic device 101, connected to the system C 102a and the memory 102b CSl Chip select of the memory 102b of the electronic device 101 CS2 Chip select of the system IC 102a of the electronic device 101 CS3 of the battery pack 1 Chip Select of Communication Circuit 9 Power Supply to Memory 102b of Vcc Electronic Equipment Device 101 Power Supply to Memory 102b of GND Electronic Equipment Device 101 When the battery pack 1 tries to communicate with the electronic equipment device 101, first Starting up the power supply Vcc of the circuit involved in signal, i.e. it is necessary to supply power from the battery pack 1 to the electronic apparatus 101. To raise Vcc, the transistors 9a and 9b of the communication circuit 9 are turned on by the output from the determination circuit 13 in the battery pack 1 as shown in FIG.
As a result, Vcc of the main body portion 9c of the communication circuit 9 is raised, and Vcc is supplied from the communication terminal 10 of the battery pack 1 to the communication terminal 10a of the electronic device 101. In addition,
The communication circuit 9 may be provided with a circuit for limiting the current such as a fuse. After Vcc is started in this way, the battery pack 1 uses the CSl of the communication terminal 10 for the electronic device 1
01, the memory 102b in the circuit 102 is selected, and DAT
By using Al, it is designated to read the model-specific information of the electronic device 101 stored in the memory 102b, so that the electronic device 101 reads the information. The read information is from DATA2 of the communication terminal 10a of the electronic device 101 to DATA of the communication terminal 10 of the battery pack 1.
2 is returned to the determination circuit 13 via the main body 9c of the communication circuit 9. The determination circuit 13 in the battery pack 1 determines from the model-specific information whether the electronic device 101 connected to the battery pack 1 is suitable for being connected to the battery pack 1. Data for this determination is stored in the memory 13b of the determination circuit 13, and the microcomputer 13a refers to the model-specific information from the electronic device 101 and the data of the model-specific information in the memory 13b to make the determination. I do.

If the judgment result is that the judgment result does not match the connection, the transistor 1 of the power supply switching circuit 15 is judged.
5a and 15b are turned off to reduce Vcc and the communication circuit 9
In addition to outputting a judgment output that suppresses power consumption in
The internal microcomputer 13a reduces the clock frequency to a low frequency, and the microcomputer 1
A transition is made to a low power consumption mode in which power consumption in 3a is suppressed. In addition, in the determination circuit 13, the output of the attachment / detachment detection circuit 8 is HI.
Since the low power consumption mode shifts to the normal operation mode only when the GH output changes to the LOW output, the normal operation mode does not shift until the battery pack 1 and the electronic device 101 are separated and reconnected.

The determination circuit 13 reduces Vcc in the same manner as described above to suppress the power consumption in the communication circuit 9 if the determination result is suitable for the connection, while the device 101
The connection switching circuit 7 is instructed to turn on the switching control circuit 6 in order to discharge and output the charge from the cell 5. After that, the switching control circuit 6 that has been turned on short-circuits the cell 5 and the positive electrode terminal 2, so that a potential difference appears between the positive electrode terminal 2a and the negative electrode terminal 3a of the electronic device 101, and the electronic device 101 becomes the battery pack 1 Can be used as a power source. When the battery pack 1 is separated from the electronic device 101, the output of the attachment / detachment detection circuit 8 changes from LOW to HIG.
Change to H output. When the determination circuit 13 senses this change, the determination circuit 13 instructs the connection switching circuit 7 to open the switching control circuit 6. Then, the positive electrode terminal 2 of the battery pack 1 is opened in any circuit, so that no potential difference appears between the positive electrode terminal 2 and the negative electrode terminal 3. Then, the microcomputer 13a of the determination circuit 13 drops the clock frequency to a low frequency so that the microcomputer 13a itself shifts from the normal operation mode to the low power consumption mode to minimize the power consumption there. To do.

The operation of the decision circuit 13 will be described with reference to the flowchart of FIG. The operation is started from step S1-O, and the operation mode when the power is turned on for the first time in S1-1 is set to the low current consumption mode or the output to the connection switching circuit 7 is set to the initial value. When initialization is completed, step S
Moving to 1-2, the output from the attachment / detachment detection circuit 8 is read.
In step Sl-3, it is determined whether the value read in step S1-2 has changed from LOW output to HIGH output. If it has changed from HIGH output to LOW output, proceed to step S1-4. If it has not changed, return to step S1-2 and continue to step S1 until a change appears.
-2 and S1-3 are repeated. In S1-4, the determination circuit 13 is shifted from the low power consumption mode to the normal operation mode. This enables high-speed control. Then, in step S1-5, the power supply switching circuit 15 is activated to supply power to the communication circuit 9. Then, power is supplied to the communication circuit 9, and the transistor 9a,
9b is started up, and the main body 9c is powered on.
The battery pack 1 is ready for communication with the outside. When communication becomes possible, in step S1-6, the electronic device 101
From the memory 102b in the circuit 102 of the electronic device 10
The model-specific information of No. 1 is read. Then, in step S1-7, it is determined whether the battery pack 1 and the electronic device 101 are suitable for connection. When it is determined in step S1-7 that the conditions match, the switching control circuit 6 is turned on in step S1-8, and the power of the electronic device 101 is supplied from the battery pack 1. If it is determined in step S1-7 that the power supply does not match, in step S1-9 the power supply switching circuit 1
5 is turned off, and the power supply of the communication circuit 9 is turned off. Then, in step S1-10, the operation mode is changed to the low current consumption mode, and then step S1-2 is entered to wait until the next connection is made. The electronic device 101 is a battery pack 1.
In many cases, the cell 5 in the battery pack 1 is charged by the following method.

The battery pack 1 is installed in the electronic device 101
When connected before the C / DC converter 103 When the AC / DC converter 103 is connected while power is being supplied from the battery pack 1 to the electronic device 101, the electronic device shown in FIG. The system IC 102a in the internal circuit 102 of the device 101 obtains information that the AC / DC converter 103 is connected. Then, the system IC 102a does not need to be supplied with power from the battery pack 1, so that the switching control circuit 6 of the battery pack 1 is turned off by communication to the determination circuit 13 of the battery pack 1 by the communication. When the determination circuit 13 of the battery pack 1 that has received the notification notifies the connection switching circuit 7 to turn off, the connection switching circuit 7 is instructed to turn off. Then, the cell 5 cannot serve as a power source for the device 101 to discharge the electric charge. Thus, after the battery pack 1 is connected to the device 101 but separated from the device 101 in terms of power supply, the determination circuit 13 of the battery pack 1 uses the voltage detection circuit to charge the cells 5. At 11, the voltage of the cell 5 itself is read. If the read voltage is a voltage required to charge the cell 5, the switching control circuit 6 is turned on so that the cell 5 is charged. Although a very small resistance for measuring the voltage of the cell 5 is required between the cell 5 and the switching control circuit 6, this resistance is not particularly shown.

A battery pack 1 is installed in the electronic device 101
When connecting later than the C / DC converter 103 In a state where the electronic device apparatus 101 is powered by the AC / DC conversion output from the commercial power source such as the AC / DC converter 103 as shown in FIG. When the battery pack 1 is connected to the electronic device 101 later, the battery pack 1 uses the communication in the internal determination circuit 13 as described above, and the memory 102a in the circuit 102 of the electronic device 101 is used.
Read the model-specific information from. Judgment circuit 1 of battery pack 1
3, when it is determined from the read model-specific information that the battery pack 1 is compatible with the connection of the electronic device circuit 101, the system IC in the circuit 102 of the electronic device apparatus 101.
102a is inquired using the communication circuit 9 whether or not there is a request for the battery pack 1. At this time, in the system IC 102a on the electronic device 101 side, the internal circuit 102 is AC / DC.
Since the information that the power is supplied from the commercial power source such as the converter 103 can be obtained, the determination circuit 13 of the battery pack 1 is notified that the battery can be charged. Upon receiving this notification, the determination circuit 13 reads the voltage of the cell 5 by the voltage detection circuit 11, and if the read voltage is a voltage that requires charging of the cell 5, turns on the switching control circuit 6 to turn on the cell 5. Control to charge.

Second Embodiment FIG. 9 shows the operation of the determination circuit 13 when the battery pack 1 according to the second embodiment of the present invention is connected to the electronic device 101 before the AC / DC converter 103. A flow chart for explaining the above is shown. Starting from step S2-O, the determination circuit 13 reads the communication command from the electronic device 101 through the communication circuit 9 in step S2-1. In the flow chart, the communication is read before the operation is performed, but in reality, the electronic device 101
When data is transmitted from the system IC 102a on the side, the determination circuit 13 on the battery pack 1 side preferentially performs the process. The system IC 102a on the electronic device 101 side and the determination circuit 13 on the battery pack 1 side are connected via CS3 of the communication terminal 10.10a, and the system IC 102a on the electronic device 101 side is the determination circuit on the battery pack 1 side. When transmitting data to 13, the system IC 102a turns on CS3. The determination circuit 6 of the battery pack 1 operates as a system IC 102 when CS3 operates.
Data from a is received from DATA2 and analyzed. In step S2-2, it is determined whether or not the data is a command that the AC / DC converter 103 is connected. Command is AC / DC converter 103
If is connected to step S2-3,
Otherwise, the process returns to step S2-1 to wait for the next command. In step S2-3, the AC / DC converter 1
Since 03 is connected, the connection switching circuit 7 is instructed to turn off so as to open the switching control circuit 6 in order to disconnect the cell 5 of the battery pack 1 from the power supply to the electronic device 101. As a result, the cell 5 is separated from the power line of the electronic device 101. In step S2-4, the voltage of the cell 5 is read via the voltage detection circuit 11. Then, in step S2-5, it is determined whether the cell 5 has a voltage required to be charged, based on the read value. If the cell 5 needs to be charged, the connection switching circuit 7 is instructed to be turned on in order to turn on the switching control circuit 6 in step S2-6, and charging is performed. If it is not necessary to charge the cell 5, the connection switching circuit 7 is instructed to turn off in order to turn off the switching control circuit 6 in step S2-7. When the cell 5 needs to be charged, the voltage of the cell 5 is sequentially read by the voltage detection circuit 11 and the charging is repeated.

FIG. 10 shows a flowchart for explaining the operation of the determination circuit 13 when the battery pack 1 according to the second embodiment of the present invention is connected after the AC / DC converter 103. Starting from step S3-O, the processing from step S1-0 to step S1-11 is performed until step S3-O. Step S
3-1 System IC 10 of electronic device 101
From 2a, the determination circuit 13 of the battery pack 1 detects that the battery pack 1
Asks if there is no command for using communication.
If there is a command, the type will be returned. If the command is a chargeable command in step S3-2, the process proceeds to step S3-3. If the command is not a chargeable command, the process proceeds to S3-7 and the process for other commands is performed. In step S3-3, the voltage of the cell 5 is detected using the voltage detection circuit 11 to detect whether the cell 5 needs charging. After detecting the voltage of the cell 5, it is determined in step S3-4 whether the cell 5 needs to be charged. If the cell 5 needs to be charged, in step S3-5, the connection switching circuit 7 is instructed to turn on the switching control circuit 6, and the cell 5 is charged. If it is not necessary to charge the cell 5, step S3-
6, the process is ended by giving an instruction to turn off the switching control circuit 6 to the connection switching circuit 7 to turn off the switching control circuit 6. When the cell 5 is charged, the voltage of the cell 5 is sequentially detected by the voltage detection circuit 11
To read and repeat charging of cell 5.

In addition, the battery pack 1 has a date / time counting circuit 1 such as an RTC for counting the date / time of charging of the cell 5.
2 is provided. The determination circuit 13 is the date / time counting circuit 12
Is used to store the last charging date and time of the cell 5 in the non-volatile memory 13b. The date / time counting circuit 12 is constantly receiving power from the cell 5 and continuously counts the date / time when the cell 5 has an electric charge. When charging the cell 5,
The previous charging date and time is read from the non-volatile memory 13b, and a limitation is set so that the cell 5 is charged if there is a certain period between the current date and time and the previous charging date and time. After charging the cell 5, the charging date and time of this time is written in the nonvolatile memory 13b to update the charging date and time to be stored. The nonvolatile memory 13 in the determination circuit 13
If the date and time of the date and time counting circuit 12 is older than the date and time read from b, it is determined that the cell 5 has been completely discharged and the date and time has not been counted, and it is provided in the electronic device 101. The system IC 102a issues an instruction to read the date and time and transfer it to the battery pack 1 from the circuit for counting the date and time.

Third Embodiment FIG. 11 shows a flowchart for explaining the operation of the determination circuit 13 in the third embodiment of the present invention. The operation here is performed when the determination circuit 13 determines whether to charge the cell 5. Starting from step S4-0, in step S4-1, the determination circuit 13 reads the date and time counted by the date and time counting circuit 12 and the previous charging date and time from the nonvolatile memory 13b. Then, step S4-2
Then, the two date and time are compared and the date and time counting circuit 12
If the read date and time is older than the previous charge date and time read from the non-volatile memory 13b, step S4-3.
Then, the date and time is obtained from the electronic device 101 and set as the current date and time. If the date and time read from the date and time counting circuit 12 is newer than the previous charging date and time read from the non-volatile memory 13b, the process proceeds to step S4-4. Step S4-4
Then, if the two date / time periods are not equal to each other to some extent, the process proceeds to step S4-5 to perform the charging process. If the period is not met, the charging process is not performed so that the cell 5 is not charged in a short period of time. When the cell 5 is charged, the current charging date and time of the cell 5 is written in the non-volatile memory 13b in the determination circuit 13.

FIG. 12 is a diagram showing a power supply line of the switching control circuit 7. The switching control circuit 7 includes a power supply OR circuit 16 that controls the input of the power supply, and a step-up / down circuit 14 that keeps the power supply voltage of the switching control circuit 7 constant. The power supply OR circuit 16 uses a diode having a small voltage effect so that power can be taken from the positive terminal 2 or the cell 5. The power supply OR circuit 16 can take power from the cell 5 when only the battery pack 1 is connected, and when the cell 5 is completely discharged, the AC / DC converter 1 is added to the electronic device 101.
When 03 is connected, it can be taken out from the electronic device 101. Even if the battery pack 1 is connected to the electronic device 101,
When the C / DC converter 103 is connected, the voltage on the side of the electronic device 101 is higher, so that the voltage is supplied from the side of the electronic device 101 and is not supplied from the side of the cell 5.

[0035]

As described above, according to the present invention, the following effects can be obtained.

According to the invention of claim 1, the external device connected to the battery pack obtains data on the suitability of the connection from the external device side using the communication means, and the suitability of the connection is judged by the judging means, and the battery pack is connected. Since the battery pack is discharged when it is determined to be compatible, it is possible to effectively prevent the deterioration of the cell performance when the battery is discharged to an external device whose connection is not compatible.

Since it is possible to charge the cells of the battery pack when it is determined that the connection is suitable using the communication according to the invention of claim 2, even if a voltage is suddenly applied between the positive electrode and the negative electrode, Therefore, it is possible to effectively prevent the cells from being charged under the conditions other than the charging conditions.

According to the third aspect of the invention , the charging of the cell can be managed based on the counting date and time of the date and time counting means and the charging date and time stored in the determining means, so that the charging is repeated even though the cell is fully charged. It is possible to effectively prevent the performance of the cell from being deteriorated.

According to the invention of claim 4 , the charging can be stopped by the command from the external device through the communication with the external device, so that the charging of the cell can be controlled according to the intention of the user.

According to the invention of claim 5, the power source of the determining means for determining whether or not to charge the battery is obtained from the external device. Therefore, even when the charge capacity of the cell is remarkably reduced, the determining means communicates with the external device. The cell can be charged by the communication.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of a battery pack and an electronic device device according to a first embodiment of the present invention.

FIG. 2 is a schematic perspective view showing an example of use of the battery pack and the electronic device of FIG.

FIG. 3 is a schematic perspective view of the battery pack of FIG.

FIG. 4 is a schematic perspective view showing an example of use of the battery pack, AC / DC converter, and electronic device of FIG.

5 is a block diagram of an internal power supply circuit of the battery pack of FIG.

6 is a block diagram of the determination circuit of FIG.

FIG. 7 is a circuit block diagram relating to communication between a battery pack and an electronic device.

FIG. 8 is a flowchart for explaining the operation of the determination circuit according to the first embodiment.

FIG. 9 is a flowchart for explaining the operation of the determination circuit according to the second embodiment.

FIG. 10 is a flowchart for explaining the operation of the determination circuit according to the second embodiment.

FIG. 11 is a flowchart for explaining the operation of the determination circuit according to the third embodiment.

FIG. 12 is a block diagram of another power supply circuit in the battery pack.

FIG. 13 is a block diagram of a conventional battery pack and electronic device.

[Explanation of symbols]

 1 Battery Pack 2 Positive Terminal 3 Negative Terminal 4 Control Terminal 5 Cell 6 Switching Control Circuit 7 Connection Switching Circuit 8 Desorption Detection Circuit 9 Communication Circuit 10 Communication Terminal 11 Voltage Detection Circuit 12 Date / Time Count Circuit 13 Judgment Circuit 14 Buck-Boost Circuit 15 Power Switching Circuit 16 Power supply OR circuit 101 Electronic equipment device 102 Electronic equipment device circuit 103 AC / DC converter

Claims (5)

[Claims] 1. A communication means for communicating information about charging with an external device, and a judging means for judging whether or not the connection to the external device is appropriate based on the information, wherein the judging means is suitable for connection. A battery pack, wherein control is performed to discharge the electric charge from the cell to the external device determined to be. 2. A communication means for communicating information about charging with an external device, and a judging means for judging suitability of connection to the external device based on the information, the judging means adapted for connection. A battery pack, wherein control is performed to charge a cell from the external device determined to be. 3. A date / time managing means and a determining means for storing a previous charging date / time of the cell, wherein the determining means is a cell based on the management date / time by the date / time managing means and the previous charging date / time. A battery pack, characterized in that it is determined whether or not to charge the battery. 4. A communication means for communicating with an external device is further provided, and the determination means relates to charging of a cell based on communication from the external device via the communication means. The battery pack according to claim 3, wherein the battery pack responds to an instruction. 5. The cell so that the power of the judging means can be obtained from the external device so that communication can be performed between the judging means and the external device even when the charge capacity of the cell is significantly reduced. The battery pack according to claim 2, wherein the battery pack can be charged.